@Nonilex I would not put it past Trump or his team to want to do something like this, even making sure people in the audience were shot.
HOWEVER
There is no way in hell they would have executed it so well. Even the best sniper is not going to be to guarantee they could shoot someone’s ear like that without putting him at risk, and Trump would never purposefully allow himself to be in such a risky situation where he could just as easily be shot and hurt or killed.
People’s reactions in a shooting are going to be all over the place as they may or may not pick up on what is happening and may not really know what to do. All the people talking about odd reactions from the audience are doing so with hindsight.
I think this truly was a failed assassination attempt that worked out in the best possible way for Trump. Like most of his life, he just fell into it by sheer luck.